Welcome to the MacNN Forums.

If this is your first visit, be sure to check out the FAQ by clicking the link above.
You may have to register before you can post: click the register link above to proceed.
To start viewing messages, select the forum that you want to visit from the selection below.

In addition to offering the first consumer smartphones with a 64-bit processor, Apple's iOS 7 update has apparently become the first major commercial software to be released with a working implementation of "multipath TCP" (MCTCP). The technology allows devices to stay connected to the Internet over both Wi-Fi and 3G or LTE simultaneously, allowing each to act as a fallback to the other in cases of weak signal. It can also maintain certain kinds of connections over Bluetooth or Ethernet as well, using all connections at once if needed.

The technique does not require any additional or advanced hardware, meaning all iPhones that can run iOS 7 can utilize the technology for more reliable connections. While the most common use would be to allow cellular data to seamlessly keep a faltering Wi-Fi connection alive without losing any data, it has other applications as well for areas like telephony and IP TV. Apple's implementation is evident in Siri, which under iOS 7 can continue communicating with Apple's servers to assist in voice recognition even when Wi-Fi service is intermittent.

First implemented on the Linux kernel, the technology is intended to create more robust connections that better utilize local networks, improve throughput and increase reliability by allowing networks to instantly work around any path failures. Under current TCP technology, if a connection falters (such as walking out of range of Wi-Fi), the session is ended and must be restarted (though Apple has long used a "handshake" technology to make 3G/LTE resumption of dropped sessions relatively painless).

MCTCP allows the simultaneous use of multiple IP addresses or interfaces, meaning that existing application "see" only a single TCP connection and thus do not require any modifications. A video of the technology (seen below) demonstrates an SSH session being connected simultaneously through Ethernet, Wi-Fi and 3G. The session continues uninterrupted as researchers turn off one, then another of the connections.

@ coffeetime.
They mention it at the end of the 1st and last paragraph. From the looks of it, wifi is the primary target, but it would appear that any major network connection will work. I'm hoping it does. Using an iPad via ethernet would be easier troubleshooting some issues for work. Lugging the old company laptop around that takes for ever to do anything is a bit of a pain.

@ coffeetime.
They mention it at the end of the 1st and last paragraph. From the looks of it, wifi is the primary target, but it would appear that any major network connection will work. I'm hoping it does. Using an iPad via ethernet would be easier troubleshooting some issues for work. Lugging the old company laptop around that takes for ever to do anything is a bit of a pain.

They mention it as a feature of multi path TCP, not as one of the iPad.

iPad would need to support USB --> Ethernet dongles via the camera connection kit for that to be possible. I don't believe it does at this point.

How do I shut it off? I don't need Verizon squeezing me anymore than they already to.

This would only happen when there is no valid network path to the internet on a wireless network. I don't think it will start using the cell network when the wireless network is simply not working properly/optimally while still issuing a valid IP.